1. Field of the Invention
The present invention relates to an extrusion nozzle arrangement and to a method for the production of an extruded product and, more particularly, to a novel multiple nozzle arrangement and method through which there can be fabricated a comestible such as, for example, a multi-layered slab of a meat analogue product, wherein the extrusion of a solution, slurry or emulsion through the nozzle orifice can be controlled so as to provide for an extruded layered product resembling natural bacon in its appearance.
Although the invention is contemplated for utilization in the fabrication of various types of products, it has particular application to the formation of a comestible, such as a bacon-like meat analogue, wherein a plurality of solutions, emulsions or slurries, some of which may have differing rheological properties and consistencies, are extruded through separate nozzles to form a multi-layered slab internally configured to provide a random pattern simulating natural bacon.
In essence, the bacon-like appearance is achieved in that each inventive extrusion nozzle includes a narrow, elongate bottom outlet orifice arranged to extend transversely above a continually moving, essentially horizontal conveyor belt, and wherein the extruded layer of solution, slurry or emulsion which is a constituent of the meat analogue product is extruded through the orifice at relatively low pressures and temperatures and deposited onto a conveyor belt in the form of a continuous layer. In order to impart a predetermined or patterned configuration to the cross-section of the solution layer which is extruded onto the conveyor belt, an insert strip is arranged within the nozzle above the orifice and coextensive with the length thereof, which includes projections extending across the path of flow of the solution or slurry extruded through the orifice, with such projections being positioned in a predetermined manner along the insert strip and dimensioned to produce either restrictions or directional changes in the flow of the extrudate egressing from the nozzle orifice. An arrangement of a plurality of extrusion nozzles spaced in essentially parallel relationship along the path of movement of the conveyor belt and extending transversely across the conveyor belt, sequentially extrudes layers formed from different solutions, slurries or emulsions constituting components of the meat analogue product in superposition upon the layer extruded by the preceding nozzle to thereby form a multi-layered slab. By selecting the configuration of the flow restricting or redirecting pattern of the insert strip of each subsequent nozzle to compensate for the variations in the layer configuration produced by the insert strip of the preceding nozzle, a predetermined random pattern can be established between each of the extruded superimposed layers so as to thereby simulate the random pattern of the internal fibers and constituents of natural bacon, or any other type of pattern representative of a product or comestible which is simulated through the present invention.
Although numerous extrusion apparatuses and nozzles, and various processes for producing meat analogue products and similar comestibles are currently known, these are generally complex and expensive in nature; requiring numerous moving structural parts which are readily subject to wear and, consequently, are of a relatively short life-expectancy; as well as requiring greater maintenance and move time and/or labor for cleaning. Moreover, with these structural parts it is frequently difficult to maintain the necessary degree of accuracy.
2. Discussion of the Prior Art
Thus, among apparatuses and methods relating to the fabrication of meat analogue products through extrusion is that disclosed in Wenger et al. U.S. Pat. No. 4,099,455 in which a vegetable protein-water mixture or emulsion is treated and then extruded through the intermediary of various screw-type extruding devices and nozzle arrangements. These arrangements are of a relatively complex nature requiring numerous moving parts which render the apparatus and method expensive and cumbersome. Moreover, the meat analogue product produced through this method does not afford the degree of controllability over the interior structure and appearance of the meat analogue product for precise simulation of the natural product, such as sliced bacon.
Similarly, Wenger et al. U.S. Pat. No. 3,970,761 disclose a method of extruding a vegetable protein based meat analogue product which, analogous to Wenger et al. U.S. Pat. No. 4,099,455, does not afford the degree of control over the appearance of the meat analogue product as a natural food, while concurrently necessitating the use of complex apparatus in effectuating the extrusion method.
Jernigan U.S. Pat. No. 3,724,984 discloses an extrusion apparatus in which a confection may be mixed within a nozzle to a desired degree. This apparatus would not appear to be unduly applicable to the fabrication of a meat analogue product possessing the controlled internal pattern which will simulate natural bacon.
Bone et al. U.S. Pat. No. 4,235,935 disclose a method and apparatus for producing a continuous strip of simulated bacon in which three differently colored doughs are combined into a strip containing three or more distinct differently colored zones, wherein such simulation of natural bacon is afforded by an emulsion which is unstable during cooking and which will distort the individual strips to simulate a random internal coloring pattern normally found in natural sliced bacon. Again there is no disclosure of an extrusion nozzle arrangement or method which will provide for the controlled patterning of the meat analogue product to precisely simulate natural bacon.
Ziminski et al. U.S. Pat. No. 4,197,324 merely disclose the fabrication of a meat-like product such as natural bacon, by providing alternating zones simulating lean and fat strata and which the variations in appearance between the layers are produced during the cooking and resultant crinkling of the product.
Cheney U.S. Pat. No. 4,196,222 discloses a process for the preparation of meat and bacon analogues wherein the combination of various phases in a random manner can be effected to simulate the internal composition and physiology of natural cooked bacon. There is no disclosure of any nozzle structure which will impart the natural appearance to a bacon-like meat analogue product in a controlled random manner without the utilization of moving mechanical components, such as stirrers, during the extrusion of the individual layers of the bacon analogue product slurry.
Ziminski et al. U.S. Pat. No. 4,166,138 merely disclose dough being shaped into a flat ribbon adapted to resemble a bacon-like product, in which random coloring of the product is effected by mixing colored and uncolored doughs intermittently or periodically in a generally random manner. This process does not provide for the separate extrusion of a plurality of layers representing individual lean and fat strata in bacon strips which are thereafter adapted to be combined into a slab which is then processed into individual natural bacon-simulating strips.